2,5-Dimethylfuran (DMF) has great potential for use and application as a biofuel or liquid fuel. First, it has a nearly ideal boiling point (92° C.), which is about 14° C. higher than ethanol's boiling point (78° C.). Second, it has a high energy density (30 kJ/cm3), and a high research octane number (RON=119), making it comparable to gasoline (Y. Román-Leshkov, C. J. Barrett, Z. Y. Liu, J. A. Dumesic, Nature 2007, 447, 982-985). Furthermore, DMF is immiscible with water and easier to blend with gasoline than ethanol, which is currently biofuel. 2,5-Dimethylfuran (DMF) is a heterocyclic compound with the following formula:

Several methods are known in the art to produce DMF. U.S. Pat. No. 2,098,592 discloses a process to synthesize DMF by pyrolyzing acetone at a temperature above 700° C. for less than a second, and then immediately cooling the reaction gases in a liquid medium. DMF can be isolated from the resulting liquid mixture. In another example, U.S. Pat. No. 2,470,070 discloses a process to synthesize DMF by heating hex-3-en-5-yn-2-ol to 100° C. in the presence of a mercuric catalyst to form DMF. Yet another example is the catalytic conversion of fructose to DMF (Y. Román-Leshkov, et al., Nature 2007, 447, 982-985); however, this process requires two separate reactions. First, fructose is dehydrated to 5-(hydroxymethyl)fufural (HMF), catalyzed by H2SO4. Then, HMF is converted to DMF using a CuRu/C catalyst, and H2 at high temperature (220° C.) and high pressure (6.8 bar). In this process, the HMF intermediate from the first step has to be isolated and purified before processing to the second step.
There remains an unmet need for new methods to produce DMF in a one-pot process, using a “green” synthetic route that does not require the use and generation of hazardous substances, and the generation of unwanted waste. The methods disclosed herein address these unmet needs.